The present invention relates to thienopyridine derivatives which are useful as an immunoregulator and for the prevention and treatment of osteoporosis.
Thienopyridine derivatives represented by Formula (A), possess the 4-hydroxythieno[2,3-b]pyridin-6-one skeleton and are described in J. Chem. Res. (S), 214 (1985) and J. Chem. Res. (S), 122 (1986): ##STR2## wherein R.sup..smallcircle. represents hydrogen or methyl and Y represents hydrogen or ethoxycarbonyl.
Furthermore, thienopyridine derivatives represented by Formula (B), possess the 7-hydroxythieno[3,2-b]-pyridin-5-one skeleton, and are described in J. Chem. Res. (S), 6 (1980) and J. Chem. Res. (S), 84 (1984): ##STR3## wherein R.sup..smallcircle. represents hydrogen or methyl and Y represents hydrogen, ethoxycarbonyl, nitrile, acetyl or the like.
In compounds (A) and (B), their pharmacological acitivities are unknown.